Hydrofluorocarbon (HFC) products are widely utilized in many applications, including refrigeration, air conditioning, foam expansion, and as propellants for aerosol products including medical aerosol devices. Although HFC's have proven to be more climate friendly than the chlorofluorocarbon and hydrochlorofluorocarbon products that they replaced, it has now been discovered that they exhibit an appreciable global warming potential (GWP).
The search for more acceptable alternatives to current fluorocarbon products has led to the emergence of hydrofluoro-olefin (HFO) products. Relative to their predecessors, HFOs are expected to exert less impact on the atmosphere in the form of a lesser detrimental impact on the ozone layer and their generally lower GWP. Advantageously, HFO's also exhibit low flammability and low toxicity.
As the environmental, and thus, economic importance of HFO's has developed, so has the demand for precursors utilized in their production. Many desirable HFO compounds, e.g., such as 2,3,3,3-tetrafluoroprop-1-ene (HFO-1234yf) or 1,3,3,3-tetrafluoroprop-1-ene (HFO-1234ze), may typically be produced utilizing feedstocks of chlorocarbons or chlorofluorocarbons, and in particular, chlorinated and/or fluorinated propenes.
Unfortunately, these chlorinated and/or fluorinated propenes may have limited commercial availability, and/or may only be available at potentially prohibitively high cost, due at least in part to the complicated, multi-step processes typically utilized in their manufacture. Furthermore, although simplified, one-step processes have been developed for the manufacture of chlorinated and/or fluorinated propenes, these processes have limited commercial applicability due to their limited throughput. Whether multi-step or one-step, many of the conventional manufacturing processes for the production of chlorinated and/or fluorinated propenes may typically result in the formation of large quantities of reaction by-products that must then be separated from the product and disposed of, typically at great expense, further limiting their commercial potential.
It would thus be desirable to provide improved processes for the production of chlorocarbon precursors useful in the synthesis of HFO's. More particularly, such processes would provide an improvement over the current state of the art if they were less costly not only in materials, but in time expenditure. Improvements in reaction productivity, selectivity and/or process throughput that could be provided without substantial detrimental impact on expense and/or safety concerns associated with the process would also provide commercial advantage.